Although the NSA is expected to cut down metadata collection, the telecom groups will still keep all the records. It seems like nothing personal, but the technical character of phone calls could surprise with the abundance of hidden material.

In a fact sheet published last week, the Obama administration pledges changes to the National Security Agency’s bulk telephony metadata program.

One of the expected concessions to civil society is the promise to leave records at the telephone companies, so that the government would allegedly be able to obtain them only in an emergency situation. But in the cold light of the day, records will still be kept. So, what could the ‘metadata’ –information on personal phone calls, claimed to contain no names or content – reveal to the NSA or just to the people who have access to them?